Multicentric Plasma Cell Castleman’s Disease associated with POEMS Syndrome: CT Findings MIng-YI HSu1 KOOn-KwAn ng1,2 SHEung-FAT KO3 Yun-CHung CHEung1 KAr-wAI LuI1,2 JIun-JIE wAng4 SIu-CHEung CHAn1,2 SHIH-MIng Jung5 SHu-HAng ng1,2

Castleman’s disease (CD) is a rare lymphoproliferative disorder of unknown cause. In even rarer circumstances, it can be associated with POEMS (peripheral neuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and sk in changes) syndrome. We report a case of multicentric plasma cell CD with POEMS syndrome, who presented with inguinal masses and lower extremity weakness for years. Computed tomography (CT) demonstrated widespread enlarged lymph nodes with homogenous enhancement, as well as splenomegaly and gynecomastia. Recognition of the CT findings in patients with appropriate clinical settings is helpful in suggesting the diagnosis of multicentric CD associated with POEMS syndrome. Castleman’s disease (CD), also known as angiofollicular hyperplasia or benign giant lymph node hyperplasia, is a rare usually benign lymphoproliferative disorder of unknown cause [1, 2]. It was first reported as localized mediastinal lymph node hyperplasia by Castleman in 1954 [2, 3]. Clinically, it can be divided into unicentric and multicentric types. Histologically, three variants, hyaline vascular, plasma cell, and mixed, have been described. The hyaline vascular pattern subtype is the most common and usually presents as a unicentric lesion. In contrast, the plasma cell variant accounts only for approximately 10 to 20% of cases and usually presents as a multicentric form [4, 5]. POEMS syndrome is a multisystemic disorder characterized by polyneuropathy, organomegaly, endocr inopathy, monoclonal gammopathy, skin changes and various other systemic clinical signs. POEMS syndrome is a rare disorder with uncertain prevalence [6, 7]. Although the association between POEMS syndrome and CD is yet unclear, it has been reported that about 19 to 24% of patients with POEMS syndrome are associated with CD [6, 8]. The imaging findings of plasma cell CD with POEMS syndrome have scarcely been reported [4, 9]. In this report, we demonstrate the computed tomography (CT) findings of multicentric plasma cell CD associated with POEMS syndrome.